﻿/*******************************************************************************************
 * Copyright (c) 2009 Alex Robson, Rob Simmons, Craig Israel, and Rachel Twyford
 *
 * Use of this software in any form requires that you have both 
 * read and agreed to the following terms:
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the "Software"), 
 * to deal in the Software without restriction, including without limitation 
 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions: 
 *
 * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 * Redistributions in binary form must reproduce the above copyright notice, 
 * this list of conditions and the following disclaimer in the 
 * documentation and/or other materials provided with the distribution.
 * Neither the name of Nvigorate nor the names of its contributors may 
 * be used to endorse or promote products derived from this software without 
 * specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
 * DISCLAIMED. IN NO EVENT SHALL ANY CONTRIBUTOR BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * ****************************************************************************************/

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Security.AccessControl;
using System.Text;
using System.Xml.Linq;
using Nvigorate.Common;
using Nvigorate.Extensions;
using Nvigorate.Xml;

namespace Nvigorate.Logging
{
    // I used the private variables as defaults and apply them
    // via null coalesce against the element
    public class TextLogAdapter : ILogAdapter
    {
        private Severities _errorLevel = Severities.Moderate;
        private long _sizeLimit = 5120;
        private string _fileName = "errorLog";
        private int _lastindex = 0;
        private string _path = "";
        private string _delimiter = ", ";
        private string _extension = "log";
        private bool _columnHeaders = false;
        private List<string> _includeFields = new List<string>() { "severity", "machine", "user", "application", "assembly", "className", "method", "errorMessage", "exceptionText" };
        private XElement _configuration = new XElement("empty");

        private string Delimiter
        {
            get
            {
                return _configuration.GetChildElementValue("delimiter") ?? _delimiter;
            }
        }

        public Severities ErrorLevel
        {
            get 
            { 
                return (Severities)
                    Enum.Parse(typeof(Severities),_configuration.GetChildElementValue("errorLevel")
                    ?? _errorLevel.ToString()); 
            }
            set
            {
                _errorLevel = value;
            }
        }

        private string Extension
        {
            get
            {
                return _configuration.GetChildElementValue("extension") ?? _extension;
            }
        }

        private string FileName
        {
            get
            {
                return _configuration.GetChildElementValue("fileName") ?? _fileName;
            }
        }

        private List<string> IncludeFields
        {
            get
            {
                var fieldsElement = _configuration.Element("fieldList");
                if(fieldsElement == null)
                {
                    return _includeFields;
                }
                else
                {
                    return fieldsElement.Elements().Select(e => e.Value).ToList();
                }
            }
        }

        private long SizeLimit
        {
            get
            {
                var val = _configuration.GetChildElementValue("sizeLimit");
                return val == null ? _sizeLimit : long.Parse(val);
            }
        }

        private string Path
        {
            get
            {
                return _configuration.GetChildElementValue("path") ?? _path;
            }
        }

        private int Index
        {
            get
            {
                var directory = new DirectoryInfo(Path);
                var files = directory.GetFiles(string.Format("{0}*.{1}", FileName, Extension), SearchOption.TopDirectoryOnly);
                var size = files.Last().Length / 1024;
                return (size > SizeLimit) ? files.Count() + 1 : files.Count();
            }
        }

        public void LogError(string machineName, string user, string application, string assembly, string className, string method, Severities severity, string exceptionText, string errorMessage, params string[] messageParameters)
        {
            var values = new[]
                             {
                                 severity.ToString(), machineName, user, application, assembly, className, method, string.Format(errorMessage, messageParameters), exceptionText
                             };
            var lookup = _includeFields.ZipToDictionary(values);

            using(var writer = new StreamWriter(System.IO.Path.Combine(Path, string.Format("{0}_{1}.{2}", FileName, Index, Extension))))
            {
                writer.Write(
                    DelimitedBuilder.Construct(lookup
                                                   .Where(kvp => IncludeFields.Contains(kvp.Key))
                                                   .Select(kvp => kvp.Value)
                                                   .ToList(), Delimiter));
            }
        }

        public bool LoadConfiguration(XElement xml)
        {
            _configuration = xml;

            if(!Directory.Exists(Path))
            {
                try
                {
                    Directory.CreateDirectory(Path);
                }
                catch (Exception e)
                {
                    Console.WriteLine(e);
                }
            }

            return true;
        }
    }
}
